Demand for plant oil-derived solvents continues to grow due to environmental and regulatory pressures to reduce emissions of Ozone Depleting Substances (ODS), Volatile Organic Compounds (VOC) and hazardous Air Pollutants (HAP). These demands are prevalent in all primary use markets including the manufacture of paints, coatings, printing inks, adhesives, cleaning products, as well as the construction and transportation industries, among others.
A number of conventional and environmentally undesirable solvents are potential candidates for replacement with a bio-based solvent. Such conventional solvents include trichloroethylene and mineral spirits in parts cleaning and degreasing applications, hydrocarbons and chlorinated hydrocarbons in general purpose industrial and institutional cleaning formulations, hydrocarbons and methylethyl ketone in solvent carriers for removing/stripping of coatings, inks, adhesives, resins, and graffiti, methylene chloride in paint strippers, carrier solvent for paints, wood and concrete stains and corrosion protection, hand cleaners and other personal care products.
Methyl soyate (bio-diesel) is a commonly used solvent produced from renewable feedstock that finds application as a component in cleaning products. Soybean oil, soybean oil carbonate, soybean oil maleate and hydrogenated soybean oil are other soybean oil-derived solvent components for degreasing, stripping and cleaning formulations. The following references were found to be relevant to plant oil-derived solvents.
U.S. Pat. No. 5,104,567 is directed to cleaning compositions consisting of vegetable oil, such as soybean oil, suitable for removing ink from printing machines and rubber sheets.
U.S. Pat. No. 5,472,631 covers cleaning compositions consisting of vegetable oil, such as soybean oil, and emulsifying surfactants that are suitable for cleaning uncured oil-based paint and varnish from paint brushes and other painting tools.
U.S. Pat. Nos. 6,183,766 and 6,423,329 are directed to skin sanitizing and moisturizing compositions, where the moisturizing agent is selected from the group consisting of castor oil, soybean oil, maleated soybean oil, sunflower oil, cottonseed oil, corn oil, walnut oil, peanut oil, olive oil, cod liver oil, almond oil, avocado oil, palm oil and sesame oil, among others.
U.S. Pat. No. 6,376,455 covers cleaning compositions containing hydrogenated soybean oil.
U.S. Pat. No. 6,395,103 covers degreasing compositions containing 5-75% of an alkyl soyate, such as methyl soyate, and optionally soy carbonate.
U.S. Pat. No. 6,784,147 covers drain cleaning compositions consisting of soy methyl ester or methyl soyate added at 92% and an emulsifier.
U.S. Pat. No. 6,833,345 covers degreasing compositions containing soy carbonate.
U.S. Pat. No. 7,135,446 is directed to glass cleaning compositions containing a solvent degreaser, such as soybean ester, in amounts ranging from 5 to 30%.
U.S. Patent Application Publication Nos. 2006/0052266 and 2007/0243101 include cleaning compositions containing up to 30% of methyl soyate as a solvent.
U.S. Patent Application Publication No. 2006/0094627 is directed to bi-solvent compositions suitable for cleaning precision components. One of the solvents in the bi-solvent system is soy-based, such as Soyclear 1500 (available form Ag Environmental Products).
U.S. Patent Application Publication No. 2006/0260064 covers fabric laundering compositions containing esters of fatty acids, including soy methyl esters.
The entire contents and disclosures of these references are incorporated herein by reference in their entirety.
Notwithstanding the above literature, the need remains for bio-based compositions suitable for a use as a cleaner, degreaser, and paint remover, among other uses.
A conventional technique for the preparation of epoxidized methyl soyate (EMS) includes epoxidation of methyl soyate by hydrogen peroxide (or an alkyl hydroperoxide) in the presence of formic or acetic acid. Use of various other catalyst systems has been disclosed. For example, CN 101284821 teaches using an ionic liquid catalyst (such as tributylmethylammonium tetrafluoroborate or 1-butyl-3-methylimidazolium tetrafluoroborate); CN 101235021 recommends using salts of heteropolyacids as catalysts; Catalysis Letters (2008), 122(1-2), 53-56 and Journal of Molecular Catalysis A: Chemical (2006), 250(1-2), 218-225 describe the effectiveness of titanium-containing mesoporous silica catalysts; CN 101139328 covers a magnetic catalyst; and CN 1966497 is directed to sulfuric acid and aluminum sulfate catalysts. Each of these references is incorporated herein by reference in its entirety.